diff --git a/t/t4205-log-pretty-formats.sh b/t/t4205-log-pretty-formats.sh
index 26fbfde4a3..73ba5e8f0c 100755
--- a/t/t4205-log-pretty-formats.sh
+++ b/t/t4205-log-pretty-formats.sh
@@ -101,7 +101,11 @@ test_expect_failure 'NUL termination with --stat' '
 
 test_expect_success 'setup more commits' '
 	test_commit "message one" one one message-one &&
-	test_commit "message two" two two message-two
+	test_commit "message two" two two message-two &&
+	head1=$(git rev-parse --verify --short HEAD~0) &&
+	head2=$(git rev-parse --verify --short HEAD~1) &&
+	head3=$(git rev-parse --verify --short HEAD~2) &&
+	head4=$(git rev-parse --verify --short HEAD~3)
 '
 
 test_expect_success 'left alignment formatting' '
@@ -117,18 +121,18 @@ EOF
 	test_cmp expected actual
 '
 
-test_expect_success 'left alignment formatting at the nth column' '
-	git log --pretty="format:%h %<|(40)%s" >actual &&
+test_expect_success 'left alignment formatting at the nth column' "
+	git log --pretty='format:%h %<|(40)%s' >actual &&
 	# complete the incomplete line at the end
 	echo >>actual &&
 	qz_to_tab_space <<\EOF >expected &&
-fa33ab1 message two                    Z
-7cd6c63 message one                    Z
-1711bf9 add bar                        Z
-af20c06 initial                        Z
+$head1 message two                    Z
+$head2 message one                    Z
+$head3 add bar                        Z
+$head4 initial                        Z
 EOF
 	test_cmp expected actual
-'
+"
 
 test_expect_success 'left alignment formatting with no padding' '
 	git log --pretty="format:%<(1)%s" >actual &&
@@ -195,18 +199,18 @@ EOF
 	test_cmp expected actual
 '
 
-test_expect_success 'right alignment formatting at the nth column' '
-	git log --pretty="format:%h %>|(40)%s" >actual &&
+test_expect_success 'right alignment formatting at the nth column' "
+	git log --pretty='format:%h %>|(40)%s' >actual &&
 	# complete the incomplete line at the end
 	echo >>actual &&
 	qz_to_tab_space <<\EOF >expected &&
-fa33ab1                      message two
-7cd6c63                      message one
-1711bf9                          add bar
-af20c06                          initial
+$head1                      message two
+$head2                      message one
+$head3                          add bar
+$head4                          initial
 EOF
 	test_cmp expected actual
-'
+"
 
 test_expect_success 'right alignment formatting with no padding' '
 	git log --pretty="format:%>(1)%s" >actual &&
@@ -234,18 +238,18 @@ EOF
 	test_cmp expected actual
 '
 
-test_expect_success 'center alignment formatting at the nth column' '
-	git log --pretty="format:%h %><|(40)%s" >actual &&
+test_expect_success 'center alignment formatting at the nth column' "
+	git log --pretty='format:%h %><|(40)%s' >actual &&
 	# complete the incomplete line at the end
 	echo >>actual &&
 	qz_to_tab_space <<\EOF >expected &&
-fa33ab1           message two          Z
-7cd6c63           message one          Z
-1711bf9             add bar            Z
-af20c06             initial            Z
+$head1           message two          Z
+$head2           message one          Z
+$head3             add bar            Z
+$head4             initial            Z
 EOF
 	test_cmp expected actual
-'
+"
 
 test_expect_success 'center alignment formatting with no padding' '
 	git log --pretty="format:%><(1)%s" >actual &&